# CVE-2026-42879: FacturaScripts: Authenticated Remote Code Execution (RCE) via GIF Image Upload in Product Images

> Authenticated attackers can upload malicious PHP files disguised as GIFs to achieve remote code execution in FacturaScripts.

- **Severity:** Medium 6.3 (`CVSS:3.1/AV:N/AC:L/PR:L/UI:N/S:U/C:L/I:L/A:L`)
- **Exploited in the wild:** Not known
- **Login needed:** Any signed-in user
- **Attackable:** Over the internet
- **Victim action needed:** Not needed
- **Fix available:** No
- **Published:** 27 May 2026
- **Updated:** 1 Jun 2026
- **Also known as:** GHSA-vf3q-frmr-vrr9

## What is CVE-2026-42879?

CVE-2026-42879 is a medium-severity vulnerability in NeoRazorX facturascripts, published on 27 May 2026. Any signed-in user can exploit it over the network, with no action from the victim.

### Official description

FacturaScripts is an open source accounting and invoicing software. In 2025.81 and earlier, an authenticated unrestricted file upload vulnerability exists in FacturaScripts' product image upload functionality. An attacker with valid credentials can upload a PHP file disguised as a GIF image (using a GIF89a header), bypassing MIME type validation. The file is stored with its original extension, including executable extensions such as .php. The vulnerability exists the addImageAction() method of Core/Lib/ExtendedController/ProductImagesTrait.php.

Weakness: CWE-94 (Improper Control of Generation of Code), CWE-434 (Unrestricted Upload of File with Dangerous Type)

## Which versions are affected by CVE-2026-42879?

2 open source packages ship an affected version, including facturascripts/facturascripts.


| Package | Ecosystem | Affected | Fixed in |
| --- | --- | --- | --- |
| `facturascripts/facturascripts` | Packagist | All versions to 2025.81 | None |
| `facturascripts/facturascripts` | Packagist | All versions to 2025.81 | None |

## How do I fix CVE-2026-42879?

No fix has been published for CVE-2026-42879 yet. Limit exposure of the affected software until one is available.

## Is CVE-2026-42879 being exploited?

There is no known exploitation of CVE-2026-42879 in the wild and no public exploit code.

Public exploit code:

- FacturaScripts RCE Exploit - Proof of Concept  (github_poc): https://github.com/guzrex/CVE-2026-42879

## Fix prompt for AI coding agents

```text
Check this codebase for CVE-2026-42879 and fix it if it is affected.

What it is: CVE-2026-42879 is a medium-severity vulnerability in NeoRazorX facturascripts, published on 27 May 2026. Any signed-in user can exploit it over the network, with no action from the victim.
Exploitation: There is no known exploitation of CVE-2026-42879 in the wild and no public exploit code.

Affected packages and fixed versions:
- facturascripts/facturascripts (Packagist): affected all versions up to 2025.81; no fix listed
- facturascripts/facturascripts (Packagist): affected all versions up to 2025.81; no fix listed

Task:
1. Search the dependency manifests and lockfiles (for example package.json, package-lock.json, requirements.txt, poetry.lock, uv.lock, pom.xml, build.gradle, go.mod, Cargo.lock, Gemfile.lock) and any Dockerfiles for the affected packages, including transitive dependencies.
2. If an affected version is in use, upgrade it to the fixed version for its release line with the project's package manager, so the lockfile is regenerated. Prefer the smallest upgrade that fixes it.
3. If there is no fix, or the upgrade would break the build, do not guess: explain the risk and the safest workaround instead.
4. Run the tests and summarise what changed and why.
5. If nothing in the project is affected, say so and change nothing.

Reference: https://insights.sbomify.com/CVE-2026-42879/ (Markdown: https://insights.sbomify.com/CVE-2026-42879/index.md)
```

## Sources

- CVE record: https://www.cve.org/CVERecord?id=CVE-2026-42879
- NVD: https://nvd.nist.gov/vuln/detail/CVE-2026-42879
- OSV: https://osv.dev/vulnerability/CVE-2026-42879

---
From sbomify Insights: https://insights.sbomify.com/CVE-2026-42879/
Summaries are generated and may contain mistakes; the official description above is the record.